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    <title>Document</title>
    <script>
        // 将数组['red','green','blue','pink','purple']的内容反过来存放
        // 1.声明一个新数组 newArr
        // 2.把旧数组索引号第四个取过来(arr.length - 1).给新数组索引号第0个元素(newArr.length)
        // 3.我们采取递减 i--
        var arr = ['red', 'green', 'blue', 'pink', 'purple'];
        var newArr = [];
        for (var i = arr.length - 1; i >= 0; i--) {
            newArr[newArr.length] = arr[i];
        }
        console.log(newArr);
    </script>
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